(A) C2C12 myoblast cells were pre-incubated with ACh (100 nmol/l) in the presence of atropine (Atr, 10 μmol/l) or mecamylamine (Mec, 10 μmol/l) prior to exposure to hypoxia (1% O₂) for 1 h. After exposure to hypoxic condition for 12 h, the IL-1β mRNA level was determined with real time RT–PCR. N, normoxia. (B) The effects of PD98059 (PD; an ERK inhibitor, 10 μmol/l), SB203580 (SB; a p38 MAPK inhibitor, 10 μmol/l), LY294002 (LY; a PI3K inhibitor, 10 μmol/l) and SP600125 (SP; a JNK inhibitor, 10 μmol/l) on hypoxia-induced IL-1β mRNA expression in C2C12 cells were examined. mRNA expression of IL-1β in C2C12 cells cultured under normoxia (N) is used as control. *P<0.05 compared with under normoxic conditions; ^#P<0.05 compared with hypoxia; ^†P<0.05 compared with hypoxia+Ach (n=4). (C–F) Effect of ACh on hypoxia-induced activation of Akt and MAPK was examined. (G–J) Effect of donepezil on the activation of Akt and MAPK in the non-ischaemic (Con) and ischaemic (ISC) hindlimb was examined. The ratio of phosphorylated form to total protein level of each kinase is shown in the histograms (n=4). *P<0.05 compared with control, ^#P<0.05 compared with the ischaemic hindlimb without donepezil.